Processes for the preparation of the antiinflammatory agent piroxicam and intermediates leading thereto, the first of which comprises reacting N-methylsaccharin with (N-2-pyridyl)haloacetamides and alkyl haloacetates in the presence of an appropriate base to give, respectively, piroxicam and alkyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxides, intermediates which can be converted into piroxicam; and the second of which comprises reacting a novel alkyl 2-(2-methyl-3-hydroxy-2,3-dihydro-1,2-benzisosulfonazol-3-yl)-2-haloacetat e with a metal hydride to give alkyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxides, intermediates leading to piroxicam.
制备抗炎药派洛昔康及其前体的过程,第一步涉及将
N-甲基糖精与(N-2-
吡啶基)卤代乙酰胺和烷基卤代
乙酸酯在适当碱存在下反应,分别得到派洛昔康和烷基
4-羟基-2-甲基-
2H-1,2-苯并噻嗪-3-羧酸酯1,1-二氧化物,这些中间体可以转化为派洛昔康;第二步涉及将一种新的烷基2-(2-甲基-3-羟基-2,3-二氢-1,2-苯并异磺酰
脲-3-基)-2-卤代
乙酸酯与
金属
氢化物反应,得到烷基
4-羟基-2-甲基-
2H-1,2-苯并噻嗪-3-羧酸酯1,1-二氧化物,这些中间体可导向派洛昔康。